Method and apparatus for sorting particles

Abstract

A method and apparatus for sorting particles moving through a closed channel system of capillary size comprises a bubble valve for selectively generating a pressure pulse to separate a particle having a predetermined characteristic from a stream of particles. The particle sorting system may further include a buffer for absorbing the pressure pulse. The particle sorting system may include a plurality of closely coupled sorting modules which are combined to further increase the sorting rate. The particle sorting system may comprise a multi-stage sorting device for serially sorting streams of particles, in order to decrease the error rate.

1. A method of isolating a subpopulation of cells from a cell population using a microfluidic cell sorting device comprising;
 identifying cells from a population in a mixture that have a desired phenotype; and 
 isolating said cells from cells that do not have the desired phenotype using a microfluidic cell sorting device, wherein the step of isolating said cells comprises the steps of:
 conveying the mixture including cells having the desired phenotype and cells that do not have the desired phenotype through a sorting channel of the microfluidic cell sorting device, 
 using an actuator in the microfluidic cell sorting device to apply a pressure pulse to a cell having the desired phenotype to deflect the cell having the desired phenotype into a first outlet of the sorting channel while cells not having the desired phenotype flow into a second outlet of the sorting channel, and 
 absorbing the pressure pulse in the sorting channel using a buffer. 
 
 
     
     
       2. The method of  claim 1 , wherein said cell population is culture of isolated primary cells. 
     
     
       3. The method of  claim 1 , wherein the cell population is a cell culture. 
     
     
       4. A method of isolating a subpopulation of cells in a mixture to be used in cell transplantation comprising;
 identifying cells with a desired phenotype; 
 isolating said cells using a microfluidic cell sorting device, wherein the step of isolating said cells comprises conveying a mixture including cells having the desired phenotype and cells that do not have the desired phenotype through a sorting channel of the microfluidic cell sorting device, using an actuator in the microfluidic cell sorting device to apply a pressure pulse to a cell having the desired phenotype to deflect the cell having the desired phenotype into a first outlet of the sorting channel while cells not having the desired phenotype flow into a second outlet of the sorting channel, and absorbing the pressure pulse in the sorting channel using a buffer; 
 collecting the cells having the desired phenotype; and 
 using a thus isolated subpopulation of cells containing the desired phenotype in a transplantation. 
 
     
     
       5. A method of isolating a subpopulation of cells in a mixture to be genetically modified comprising,
 identifying a subpopulation of cells based on a desired phenotype in a cell population; 
 isolating said cells using a microfluidic cell sorting device, wherein the step of isolating said cells comprises conveying a mixture including cells having the desired phenotype and cells that do not have the desired phenotype through a sorting channel of the microfluidic cell sorting device, using an actuator in the microfluidic cell sorting device to apply a pressure pulse to a cell having the desired phenotype to deflect the cell having the desired phenotype into a first outlet of the sorting channel while cells not having the desired phenotype flow into a second outlet of the sorting channel, and absorbing the pressure pulse in the sorting channel using a buffer; and 
 genetically modifying cells containing the desired phenotype that have been isolated using the microfluidic sorting device. 
 
     
     
       6. A method of isolating a subpopulation of cells in a mixture comprising,
 identifying a subpopulation of cells in the mixture displaying a cell cycle stage specific marker; 
 isolating said cells using a microfluidic cell sorting device, wherein the step of isolating said cells comprises conveying the mixture including cells having the desired phenotype and cells that do not have the desired phenotype through a sorting channel of the microfluidic cell sorting device, using an actuator in the microfluidic cell sorting device to apply a pressure pulse to a cell having the desired phenotype to deflect the cell having the desired phenotype into a first outlet of the sorting channel while cells not having the desired phenotype flow into a second outlet of the sorting channel, and absorbing the pressure pulse in the sorting channel using a buffer; and 
 thereby isolating a subpopulation of cells that are in the same phase of the cell cycle. 
 
     
     
       7. The method of  claim 1 , wherein the pressure pulse is applied by deflecting a meniscus formed by fluid at an intersection between a side channel in communication with the sorting channel and a sealed chamber positioned adjacent to the side channel. 
     
     
       8. The method of  claim 4 , wherein the pressure pulse is applied by deflecting a meniscus formed by fluid at an intersection between a side channel in communication with the sorting channel and a sealed chamber positioned adjacent to the side channel. 
     
     
       9. The method of  claim 5 , wherein the pressure pulse is applied by deflecting a meniscus formed by fluid at an intersection between a side channel in communication with the sorting channel and a sealed chamber positioned adjacent to the side channel. 
     
     
       10. The method of  claim 6 , wherein the pressure pulse is applied by deflecting a meniscus formed by fluid at an intersection between a side channel in communication with the sorting channel and a sealed chamber positioned adjacent to the side channel. 
     
     
       11. A method of isolating a subpopulation of cells to be used in cells transplantation comprising the steps of:
 identifying cells with a desired phenotype; and 
 isolating said cells from cells not having the desired phenotype using a microfluidic device, wherein the step of isolating comprises using an actuator in the microfluidic device to apply a pressure pulse to cells having the desired phenotype in a channel to deflect cells having the desired phenotype into a first outlet while cells not having the desired phenotype flow into a second outlet and absorbing the pressure pulse using a buffer, 
 thereby isolating a subpopulation of cells to be used in transplantation.